An evaluation of Merino wool quality:II. An estimate of the incidence of coarse fibres in Australian Merino wool

SUMMARY Estimates of the incidence of coarse fibres and medullation were made from 1014 bales of Merino greasy wool, from the five major wool-selling centres in Australia. A full range of wool types was represented from the fault-free spinners types to the burry, dusty, inferior topmakers' types. The wool consisted of 36 processors' lots ranging from 1 to 120 bales. The mean diameter of the 36 lots was 20·7 ± 5·3 μ 2·4% of the fibre population exceeded 30 μ the incidence of medullation was 1·1%. Mean diameters of the individual lots ranged from 14·7 to 25·3 μ Twenty-one of the 36 lots had coefficients of variation of mean fibre diameter which exceeded 23%. The range of clean, oven-dried yield was 49·4–69·1%. The between-lot variation in fibre medullation was 0–3·1%. It is concluded that fibre coarseness as measured by diameter was not a problem in the wide range of wool sampled. However, the incidence of medullation is an increase on previous estimates and should be a cause of concern to breeders.